Electronic energy transfer in nearhyphen;resonant electron capture collisions of H+2with metal atoms: Radiative and nonradiative transitions

摘要

Modes of energy disposal in electron capture of H+2with metal atoms (Cs, K, Mg, and Zn) for ion velocities in the range 3ndash;7times;107cm/s are examined using combined optical and beam scattering techniques. Radiative and nonradiative transitions are observed for processes occurring under near resonant conditions. The following branching sequences are identified: Branching ratios are dependent on the vibrational state and the nuclear separation (Franckndash;Condon factors) of the H+2ion at the time of electron capture. The branching ratio decreases for the (triplet)/(singlet) formation for H2produced from reactions of vibrationally relaxed H+2ion with K or Cs. Under conditions of H+2ion relaxation, the kinetic energy of scattered atomic hydrogen following radiative decay from3Sgr;+gstate of H2increases, implying a shift in the3Sgr;+grarr;3Sgr;+ucontinuum toward longer wavelengths. The results also show that, at these velocities, the reations occur under nearhyphen;resonant conditions with vertical transitions.